The present invention relates to an air cleaning apparatus for vehicles, provided in an air conditioning duct of a vehicle for cleaning air in the vehicle to remove contaminant, particularly, cigarette smoke in a vehicle compartment.
Generally, an air cleaning apparatus used in a vehicle such as automobile, for cleaning air in a vehicle compartment has been known in the prior art. Such an air cleaning apparatus is provided in, for example, an air conditioning duct and cleans air by removing contaminant from the air in the vehicle compartment when the air circulates therein.
On the other hand, contaminant of air in the compartment includes not only fine particles and dust, but also cigarette smoke. In recent years, deodorization of bad odor of cigarette smoke has been strongly demanded in particular. Such an art in which an activated charcoal filter is disposed in an air passage so as to remove smoking odor by absorbing the odor thereto has been known.
However, cigarette smoke contains bad odor substances such as ammonia, acetic acid and acetaldehyde. Although a conventional activated charcoal filter is capable of removing acetic acid to some extent, it is not capable of removing ammonia and acetaldehyde. Thus, the conventional activated charcoal filter does not have a sufficient deodorizing effect.
Although an art of removing ammonia by neutralizing reaction by treating the activated charcoal with acid can be considered, it is not possible to obtain a sufficient deodorization effect even if this art alone is employed.